This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. xc2xa7119 from my application entitled KIMCHI REFRIGERATOR AND CONTROL METHOD THEREOF filed with the Korean Industrial Property Office on Mar. 26, 2001 and there duly assigned Serial No. 2001-15720.
1. Field of the Invention
The present invention relates in general to a refrigerator, and more particularly, to a refrigerator improved in the structure and the control method of a sensor sensing a temperature of a chamber thereof.
2. Description of the Related Art
Generally, a refrigerator is an apparatus which can maintain freshness of food by keeping a chamber at a predetermined cooling temperature, preventing the food from being spoiled. Recently, a kimchi refrigerator is also known as a kind of refrigerator, capable of exclusively preserving food such as kimchi, etc. requiring ripening and cooling.
Even if there are various kinds of refrigerators, they have a sensor sensing a temperature of a chamber and a controller controlling them based on the sensed temperature in common, in order to keep the chamber at a predetermined set up temperature.
Descriptions will be made hereinbelow with respect to a kimchi refrigerator equipped with the function of cooling and ripening by way of example.
FIG. 7 is a side sectional view of a conventional kimchi refrigerator. As shown therein, the kimchi refrigerator is comprised of an outer casing 110 forming an outward appearance and an inner casing 120 forming a chamber 111. There is formed a space to be filled with a foaming material between the outer casing 110 and the inner casing 120. Below the chamber 111 is provided a component chamber 113.
In the space to be filled with the foaming material, which is positioned between the outer casing 110 and the inner casing 120, are installed an evaporator pipe 115 and a heater 117, to surround the inner casing 120. In the component chamber 113 are accommodated a compressor 114 supplying a refrigerant to an evaporator (not shown), etc.
Further, in the space to be filled with the foaming material, which is positioned between the outer casing 110 and the inner casing 120, is provided a sensor 119 sensing an inner temperature of the chamber 111 and transmitting information of the sensed temperature to a controller (not shown). The temperature sensor 119 is contacting with an outer surface of the inner casing 120 so as to sense the temperature of the chamber 111.
In this conventional kimchi refrigerator, because the temperature sensor is contacting with the outer surface of the inner casing 120 in the space for the foaming material, it is difficult to sense a real temperature inside the chamber 111, and to react promptly to a variation of the inner temperature thereof.
That is, because the temperature sensor senses the temperature of the outer surface of the inner casing to which heat from the evaporator pipe and the heater is directly transferred, a difference between a real temperature inside the chamber and the sensed surface temperature of the inner casing is created. Moreover, where a temperature is changed, for example, by adding new food to the chamber, it takes some time for the changed temperature inside the chamber to affect the temperature of the surface of the inner casing, and therefore, the temperature is neither promptly sensed by the sensor nor controlled by the controller.
In addition, because the only one sensor is installed in the space for the foaming material between the outer casing and the inner casing, it is impossible to repair or to replace the sensor when the sensor is out of order.
Accordingly, the present invention has been made keeping in mind the above-described shortcomings and user""s need, and an object of the present invention is to control an inner temperature of a chamber by sensing a real temperature inside the chamber accurately and promptly.
This and other objects of the present invention may be accomplished by the provision of a refrigerator comprising at least one chamber and a temperature adjuster adjusting an inner temperature of the chamber, further comprising a first temperature sensor approximately sensing the temperature inside the chamber, a second temperature sensor spaced from the first temperature sensor so as to sense the real temperature inside the chamber; and a controller controlling the temperature adjuster according to the temperature sensed by the second temperature sensor when the temperature sensed by the first temperature sensor is within predetermined temperature limits of the chamber and the temperature sensed by the second temperature sensor is not within the predetermined temperature limits of the chamber.
Preferably, the first and second temperature sensors are installed at lower and upper parts of the chamber, respectively; and the controller is programmed with first and second temperature limits to be compared with the temperatures sensed by the first and second temperature sensors, respectively.
Effectively, one of the first and second temperature sensors is removably installed.
Desirably, the first temperature sensor is in contact with the bottom surface of the chamber and senses the temperature of the surface of the chamber; and the second temperature sensor is installed at the upper part of the chamber and senses the inner temperature of the chamber.
Effectively, at the upper part of the chamber are provided a sensor accommodating part accommodating the second sensor, and a sensor cover opening and closing the sensor accommodating part.
Desirably, the first and second temperature limits are different each other.
Effectively, the controller determines whether the temperature sensed by the first temperature sensor is within the first temperature limits, if the temperature sensed by the second temperature sensor is within the second temperature limits, to thereby control the temperature adjuster.
Preferably, the controller controls the temperature adjuster to allow the temperature sensed by the second temperature sensor to be within the second temperature limits, if the temperature sensed by the second temperature sensor is beyond the second temperature limits, and determines whether or not the temperature sensed by the first temperature sensor is within the first temperature limits, if the temperature sensed by the second temperature sensor is within the second temperature limits, to thereby control the temperature adjuster.
Effectively, the controller controls the temperature adjuster until the temperature sensed by the second temperature sensor is within the second temperature limits, and then determines whether or not the temperature sensed by the first temperature sensor is within the first temperature limits, to thereby control the temperature adjuster.
Effectively, the refrigerator further comprises first and second sensor indicators indicating operating states of the first and second temperature sensors; and the controller controlling the operating states of the first and second temperature sensors.
Where one of the first and second temperature sensors is determined to be abnormal, the controller allows the concerned sensor indicators to indicate abnormality thereof and determines whether or not the temperature sensed by the other normal temperature sensor is within the temperature limits of the normal temperature sensor, to thereby control the temperature adjuster.
In addition, where both the first and second temperature sensors are out of order, the controller allows both the first and second sensor indicators to indicate the abnormalities of both the first and second temperature sensors, and suspends the operation of the temperature adjuster.
The temperature adjuster comprises a cooling system cooling the chamber with a compressor, a condenser, an evaporator and a valve which circulate a refrigerant; and a heater heating the chamber.
According to another aspect of the present invention, the above and other objects may be also achieved by the provision of a method for controlling a refrigerator comprising at least one chamber and a temperature adjuster adjusting an inner temperature of the chamber, comprising the steps of sensing the inner temperature of the chamber by means of first and second temperature sensors disposed at different positions each other; determining whether or not the temperature sensed by at least one of the first and second temperature sensors is within predetermined temperature limits of the chamber, to thereby control the temperature adjuster.
Desirably, the first and second temperature sensors are installed lower and upper parts of the chamber, respectively; and the predetermined temperature limits first and second temperature limits to be compared with the temperatures sensed by the first and second temperature sensors, respectively.
Effectively, one of the first and second temperature sensors is removably installed.
Preferably, the first and second temperature limits are different each other.
Effectively, the method further comprises the step of determining whether the temperature sensed by the first temperature sensor is within the first temperature limits, if the temperature sensed by the second temperature sensor is within the second temperature limits, to thereby control the temperature adjuster.
The method further comprises the steps of controlling the temperature adjuster to allow the temperature sensed by the second temperature sensor to be within the second temperature limits, if the temperature sensed by the second temperature sensor is beyond the second temperature limits, and determining whether or not the temperature sensed by the first temperature sensor is within the first temperature limits, if the temperature sensed by the second temperature sensor is within the second temperature limits, to thereby control the temperature adjuster.
Effectively, the method further comprises the step of controlling the temperature adjuster until the temperature sensed by the second temperature sensor is within the second temperature limits, and then determining whether or not the temperature sensed by the first temperature sensor is within the first temperature limits, to thereby control the temperature adjuster.
Preferably, the method further comprises the step of checking operating states of the first and second temperature sensors and indicating the operating state of the first and the second temperature sensors by means of the first and the second sensor indicators.
Desirably, the method further comprises the step of allowing the concerned sensor indicators to indicate abnormality thereof where one of the first and second temperature sensors is determined to be abnormal, and determining whether or not the temperature sensed by the other normal temperature sensor is within the temperature limits of the normal temperature sensor, to thereby control the temperature adjuster.
Effectively, the method further comprises the step of allowing both the first and second sensor indicators to indicate the abnormalities of both the first and second temperature sensors, and suspending the operation of the temperature adjuster, where both the first and second temperature sensors are out of order.
At this time, the temperature adjuster comprises a cooling system cooling the chamber with a compressor, a condenser, an evaporator and a valve which circulate a refrigerant; and a heater heating the chamber.